The iTunes singles chart is generated based on a calculation that takes into account the ratings customers provide on a specific item as well as its sales, a member of Apple's support staff said.

The single's popularity is believed to have been bolstered by the promise that all proceeds will go to the earthquake relief effort in quake-ravaged Kaikōura.

The idea for the track came after digging up country star Dennis Marsh's 2001 gem 'Christmas in New Zealand'.

The Story team re-recorded his Kiwi classic with a bunch of stars - but were coy on who their line-up would include until Thursday night's show, when they revealed some of the big names who'd joined the ranks.

The song reflects the summer nights, jandals, playing cricket on the beach and barbeques rather than sitting by the fire and building snowmen.

Red Cross NZ Secretary General Tony Paine says the charity is appreciative of the support for those affected by the quakes.

"Combining the fun of a New Zealand-based festive song with helping our fellow Kiwis this holiday season is a great initiative - and we guarantee that 100 percent of the donations we receive will go to help the people affected."

Story is confident the song can reach the number one spot, and that celebrating a true Kiwi Christmas will resonate with the country.